Rydberg constant

https://dx.doi.org/10.1351/goldbook.R05430
Atomic fundamental physical constant R ∞ = E h 2 h c 0 = 1.097 373 1534 13 × 10 7 m −1, where E h is the Hartree energy, h the Planck constant, and c 0 the speed of light.
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